Thursday, December 18, 2008

The PING))) ultrasonic sensor

The PING))) ultrasonic sensor provides a low-cost and easy method of distance measurement. This sensor is perfect for any number of applications that require you to perform measurements between moving or stationary objects. Naturally, robotics applications are very popular but you’ll also find this product to be useful in security systems or as an infrared replacement if so desired. You will definitely appreciate the activity status LED and the economic use of just 1 I/O pin. Plus, the 3-pin header makes it easy to connect using a servo extension cable, no soldering required.

The PING))) sensor measures distance using sonar; an ultrasonic (well above human hearing) pulse is transmitted from the unit and distance-to-target is determined by measuring the time required for the echo to return. Output from the PING))) is a variable-width pulse that corresponds to the distance to the target.

• Range: 2 cm to 3 m (~0.75 in. to 10 ft)
• Supply Voltage: 5V +/-10% (Absolute: Minimum 4.5 V, Maximum 6 V)
• Supply Current: 30 mA typ; 35 mA max
• 3-pin interface (power, ground, signal)
• 20 mA power consumption
• Narrow acceptance angle
• Simple pulse in/pulse out communication
• Indicator LED shows measurement in progress
• Input Trigger: positive TTL pulse, 2 μs min, 5 μs typ.
• Echo Pulse: positive TTL pulse, 115 μs to 18.5 ms
• Echo Hold-off: 750 μs from fall of Trigger pulse
• Burst frequency: 40 kHz for 200 μs
• Dimensions: 22 x 46 x 16 mm (0.85 x 1.8 x 0.6 in)
• Operating temperature: 0 - 70 ºC